the guy they moved to was better. Utah was forced to change their QB to a guy who was absolutely not better than the guy they started the season with.
Given a choice, Utah would have gladly had Huntley playing, but couldn't due to injury and had to go with their second choice. Given the choice, BYU chose to play Wilson because they realized he was better and they absolutely wanted to be playing him against Utah. They could have played Mangum if they had wanted to.
It's completely misleading to say, "Well BYU was on their second string QB too and therefore at just as much of a disadvantage at that position." I'm not saying anything about the overall injuries to the entire team, but the QB position wasn't even close to a wash situation for the two teams.